DE in Run

I have been using food grade DE mixed in the pine shavings in my coop and PDZ under the roosts. I am very happy with the lack of odor inside the coop and was wondering if it is okay to use either product in the run as well. One run is covered and has a medium builders sand floor and the other is not covered and has a dirt floor, though our soil has a lot of natural sand. If I put it in the uncovered run would I have to change it after it rains?